In Fig. REF , we study the performance of the algorithm developed in Section  for the 3-D channel model.
The simulation parameters are set as follows: \(H_{\min }=10\)  m, \(H_{\max }=200\)  m, \(d_1=20\)  m, \(d_2=200\)  m, \(f_c=2.5\)  GHz, noise power is -93 dB. The channel model from the controller the UAV is assumed to be suburban environment. We study the performance when the channel from the UAV to the robot experiences various environments. The environment parameters are referred to [1]}. To study the importance of optimizing the height, we also show the performance when the height is fixed as \(H=100\)  m, which is denoted as `FixedH' in Fig. REF . It can be observed that the proposed joint optimization algorithm outperforms the the `FixedH' algorithm for various environments, and the performance gains increase with \(M\) , which confirms the importance of optimizing the height.
